How do I find my USPS User ID?

Register for an account at the [**USPS Web Tools registration page**](https://www.usps.com/business/web-tools-apis/welcome.htm). You will receive your User ID via email. Copy and paste it below.

Does it support international tracking?

Yes. The `track_usps_package` tool supports tracking for any valid USPS tracking number, including international shipments originating from or delivered by USPS.

What is the format for address verification?

The API requires an object with line1, city, and state metadata. Standardizing these inputs ensures the most accurate verification from the USPS database.

USPS Developer Portal MCP Server for Cursor 8 tools — connect in under 2 minutes

Name: USPS Developer Portal
Availability: InStock
Author: Vinkius

docs.cursor.com/context/model-context-protocol

Built by Vinkius GDPR 8 Tools IDE

Cursor is an AI-first code editor built on VS Code that integrates LLM-powered coding assistance directly into the development workflow. Its Agent mode enables autonomous multi-step coding tasks, and MCP support lets agents access external data sources and APIs during code generation.

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The modern way to manage MCP Servers — no config files, no terminal commands. Install USPS Developer Portal and 2,500+ MCP Servers from a single visual interface.

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Classic Setup·json

{
  "mcpServers": {
    "usps-developer-portal": {
      "url": "https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp"
    }
  }
}

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* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure

About USPS Developer Portal MCP Server

Empower your AI agent to orchestrate your entire postal logistics and address auditing workflow with the USPS Developer Portal, the official source for United States Postal Service data. By connecting USPS Web Tools to your agent, you transform complex shipping tasks into a natural conversation. Your agent can instantly verify addresses, audit package tracking statuses, and retrieve ZIP code metadata without you ever touching a shipping portal. Whether you are managing e-commerce deliveries or conducting regional address audits, your agent acts as a real-time logistics consultant, ensuring your data is always verified and precise.

Cursor's Agent mode turns USPS Developer Portal into an in-editor superpower. Ask Cursor to generate code using live data from USPS Developer Portal and it fetches, processes, and writes. all in a single agentic loop. 8 tools appear alongside file editing and terminal access, creating a unified development environment grounded in real-time information.

What you can do

Address Auditing — Standardize and verify United States addresses to ensure your shipping metadata is always grounded in official USPS records.
Advanced Tracking Control — Track real-time package statuses and access granular facility-level tracking events instantly.
ZIP Code & Routing Discovery — Cross-reference ZIP codes with city/state pairs to understand the geographic reach of your logistics.
Domestic & International Rates — Accurately calculate the real-time cost of shipping across various mail classes, weights, and global destinations.
Service Delays & Commitments — Query live delivery commitments by mail class to accurately orchestrate e-commerce fulfillment.

The USPS Developer Portal MCP Server exposes 8 tools through the Vinkius. Connect it to Cursor in under two minutes — no API keys to rotate, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.

How to Connect USPS Developer Portal to Cursor via MCP

Follow these steps to integrate the USPS Developer Portal MCP Server with Cursor.

Open MCP Settings

Press Cmd+Shift+P (macOS) or Ctrl+Shift+P (Windows/Linux) → search "MCP Settings"

Add the server config

Paste the JSON configuration above into the mcp.json file that opens

Save the file

Cursor will automatically detect the new MCP server

Start using USPS Developer Portal

Open Agent mode in chat and ask: "Using USPS Developer Portal, help me...". 8 tools available

Why Use Cursor with the USPS Developer Portal MCP Server

Cursor AI Code Editor provides unique advantages when paired with USPS Developer Portal through the Model Context Protocol.

Agent mode turns Cursor into an autonomous coding assistant that can read files, run commands, and call MCP tools without switching context

Cursor's Composer feature can generate entire files using real-time data fetched through MCP. no copy-pasting from external dashboards

MCP tools appear alongside built-in tools like file reading and terminal access, creating a unified agentic environment

VS Code extension compatibility means your existing workflow, keybindings, and extensions all work alongside MCP tools

USPS Developer Portal + Cursor Use Cases

Practical scenarios where Cursor combined with the USPS Developer Portal MCP Server delivers measurable value.

Code generation with live data: ask Cursor to generate a security report module using live DNS and subdomain data fetched through MCP

Automated documentation: have Cursor query your API's tool schemas and generate TypeScript interfaces or OpenAPI specs automatically

Infrastructure-as-code: Cursor can fetch domain configurations and generate corresponding Terraform or CloudFormation templates

Test scaffolding: ask Cursor to pull real API responses via MCP and generate unit test fixtures from actual data

USPS Developer Portal MCP Tools for Cursor (8)

These 8 tools become available when you connect USPS Developer Portal to Cursor via MCP:

calculate_domestic_rate

Calculate USPS domestic shipping rates

calculate_international_rate

Calculate USPS international shipping rates

get_delivery_commitments

Get USPS service delivery commitments and estimates

lookup_usps_city_state

Look up the city and state for a ZIP code

lookup_usps_zip_code

Look up the exact ZIP code for a specific US address

track_usps_package

Track a USPS package using a tracking number

track_usps_package_advanced

Get advanced tracking information for a USPS package

verify_usps_address

Verify and standardize a US address using USPS Web Tools

Example Prompts for USPS Developer Portal in Cursor

Ready-to-use prompts you can give your Cursor agent to start working with USPS Developer Portal immediately.

"Verify address '1600 Pennsylvania Avenue NW, Washington, DC 20500' using USPS."

"Track my package with tracking number '9400100000000000000000'."

"Lookup ZIP code for 'Seattle, WA'."

Troubleshooting USPS Developer Portal MCP Server with Cursor

Common issues when connecting USPS Developer Portal to Cursor through the Vinkius, and how to resolve them.

Tools not appearing in Cursor

Ensure you are in Agent mode (not Ask mode). MCP tools only work in Agent mode.

Server shows as disconnected

Check Settings → Features → MCP and verify the server status. Try clicking the refresh button.

USPS Developer Portal + Cursor FAQ

Common questions about integrating USPS Developer Portal MCP Server with Cursor.

What is Agent mode and why does it matter for MCP?

Agent mode is Cursor's autonomous execution mode where the AI can perform multi-step tasks: reading files, editing code, running terminal commands, and calling MCP tools. Without Agent mode, Cursor operates in a simpler ask-and-answer mode that doesn't support tool calling. Always ensure you're in Agent mode when working with MCP servers.

Where does Cursor store MCP configuration?

Cursor looks for MCP server configurations in a mcp.json file. You can configure servers at the project level (.cursor/mcp.json in your project root) or globally (~/.cursor/mcp.json). Project-level configs take precedence.

Can Cursor use MCP tools in inline edits?

No. MCP tools are only available in Agent mode through the chat panel. Inline completions and Tab suggestions do not trigger MCP tool calls. This is by design. tool calls require user visibility and approval.

How do I verify MCP tools are loaded?

Open Settings → Features → MCP and look for your server name. A green indicator means the server is connected. You can also check Agent mode's available tools by clicking the tools dropdown in the chat panel.